What is the Magna Carta, and why is it important? – Telegraph

The Magna Carta was granted 800 years ago. A series of events are taking place on the anniversary – 14 and 15 June – to mark the occasion, including a flotilla of boats sailing down the Thames and a royal appearance in Runnymede, the site of the charter’s sealing all those years ago.
So what is it, how did it come about, and what does it do today?